Description and functioning of the No.247 all-ways fuze:
The open firing cap is placed in a hard lead cylinder with a chamfered edge on the side of the firing cap. A channel is drilled through the cylinder, housing the firing pin. The firing pin has a disc in top with a chamfered edge towards the centre. A lead ball is placed in this disc. A radial hole is drilled through the firing pin, blocking it from inward movement toward the firing cap if the safety pin is stuck through. The safety pin is connected to a linen tape with a curved lead weight at the other end. The firing pin is kept away from the firing cap by a weak spring.
The hole in the fuze in which the fuze assembly is placed also has two chamfered edges in top and bottom.
Before throwing the grenade, the Bakelite cap is screwed off and discarded. The thumb is kept on the curved lead weight to avoid the grenade from premature arming. When thrown , the linen tap unrolls, pulling the safety pin from the grenade during flight. The grenade is now armed.

It does not matter in which position the grenade lands:
-Perpendicular on base: inertia will push the lead ball with the firing pin down into the firing cap.
-Perpendicular on the fuze: inertia will push the firing cap cylinder into the firing pin.
-Landing on its side: The ball, either the firing cap housing will be swung to the side due to inertia, rolling along the chamfered edges of the fuze housing. This will change a vertical movement into a horizontal one, pushing the firing pin into the firing cap housing, allowing the firing pin to ignite the firing cap.

The firing cap will initiate the detonator that explodes and blows open the sheet steel body, exposing the white phospor to the air. This will cause the Phosphor to burn and develop a thick smoke screen of white smoke.

Officially this grenade is a smoke grenade, but practically grenades with white Phospor are often used as anti-personnel grenades as they have great psychological effect caused by the burning fragments of white phospor they scatter around. These are very hard to extinguish when hitting clothing or flesh, causing horrible burn wounds.

After WW2 the British found out that greanades had corroding bodies due to inferior sheet steel used, and the grenade was taken out of service in 1948. Canadian grenades were of better steel quality and remained into service until 1950.